


Sempiternal

by oiivkawa



Category: Haikyuu!!
Genre: 5+1, Alpha Iwaizumi Hajime, Alpha/Beta/Omega Dynamics, Falling In Love, Fluff, Friends to Lovers, Getting Together, M/M, Omega Oikawa Tooru, Omega Verse, Pining, Scent Marking, Slow Burn
Language: English
Status: Completed
Published: 2018-05-27
Updated: 2018-05-27
Packaged: 2019-05-14 14:51:20
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 1
Words: 3,170
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14771733
Author URL: https://archiveofourown.org/users/oiivkawa/pseuds/oiivkawa
Summary: “Do you think I’m going to be a beta too?” Tooru asked curiously.“Doesn’t matter,” Hajime shrugged.“Why not?” Tooru glared, annoyed at being brushed off.“Because I’m going to marry you, anyway,” he stated.The journey of friendship and love over the years wherein Tooru rejects Hajime 5 times followed by the 1 time he doesn't.





	Sempiternal

**Author's Note:**

  * For [MnKrm](https://archiveofourown.org/users/MnKrm/gifts).



> thank you to my love Pinta for the title inspiration ily!

**♔♔** **1 month – [1]** **♔♔**

Oikawa Reina had been looking forward to this day for a long time. Ever since her best friend had given birth to a baby boy she had been waiting for her own to arrive. Last month, she was blessed with a son herself; Tooru, as she and her husband decided to name him. He was small, red-faced and could barely open his eyes but he laughed all the time and that brought a smile to her face. He was the second child, but something about having a son so close in age to her best friend’s own made the experience just as exciting as the first time around.

Today was the first time she and Iwaizumi Michiko were going to introduce their boys to one another, hopeful of a friendship just like their own.

“Reina,” Michiko’s voice called out from the living room.

“In here,” Reina called back, stepping away from the crib where she had just placed Tooru down for a nap. She watched him gurgle before settling back into a relaxed state, eyes closed and face happy.

“Oh, he’s sleeping,” Michiko sighed. “We can come back later.”

“No, stay,” Reina insisted. “We planned this day for too long for it to go to waste now.”

“We live down the street,” Michiko pointed out, but she walked forward, regardless.

“Why don’t we let Hajime-chan sleep with him?” Reina suggested.

“I don’t want Hajime to accidentally hurt Tooru-chan,” Michiko frowned.

Reina shook her head, insisting that Tooru was pleasant with everyone.

Hajime was quiet, but when Michiko placed him in the crib next to Tooru, he took one look at the boy next to him and giggled, waving his tiny arms about excitedly, not quite able to reach Tooru’s fingers.

“He likes him,” Michiko smiled warmly.

Tooru, still half asleep, stirred at the sound of Hajime’s giggles, felt the unfamiliar presence next to him and burst into loud tears.

“He doesn’t usually cry around strangers,” Reina frowned. “I’m so sorry,” she apologized, feeling a little embarrassed at how fussy Tooru was being, especially when it was her best friend’s son and he had no problem with anyone else.

As if reading her expression, Michiko shook her head gently. She picked Hajime up, but the baby did not like being separated from Tooru and he too started crying.

“Looks like we’ve got some trouble ahead of us,” Michiko laughed, gently rocking her son, soothing him with her scent while Reina did the same.

“Lots of trouble,” Reina whispered, eyes falling onto the way Tooru and Hajime reached for each other’s hands despite the fact that it was what had led to them crying in the first place.

 

**♔♔** **4 years – [2]** **♔♔**

“Hajime-chan!” Tooru scolded, eyes welling up.

As a baby, he hadn’t been much of a crier but at four years old, he had turned into something of a brat, as his sister liked to say.

“What?” Hajime asked, confused and a little bit wary of Tooru’s behaviour.

“Everyone in class was making fun of me and it’s your fault!” he wailed.

Their mothers had come to pick them up from pre-school, but upon seeing the upset look on Tooru’s face and the way Hajime shifted like he was hiding something, they had brought them to the park to cheer them up.

Tooru generally liked playing outside, especially with Hajime, but right now, he just wanted to go home, make a fort and hide in it forever, _alone_.

“They were not,” Hajime insisted, reaching for Tooru’s hand.

“ _Don’t_!” he cried. “Yes they were,” he added a little miserably.

They had wandered far enough to be seen by their mothers but still far enough to be alone. It was the first time Tooru had genuinely been angry with his best friend. Sure, Hajime liked to tease him by making him close his eyes and then putting bugs in his hands but at least Hajime only showed him the pretty ones like ladybugs and butterflies.

But the kids at the pre-school had been mean and he didn’t like being called things like _weak_. When they told Hajime he was too good for someone like Tooru, it made him inexplicably angry with his best friend. _Especially_ when they laughed at the way Hajime held Tooru’s hand and Hajime wouldn’t let go, even to make the laughter stop.

“You always let me hold your hand,” Hajime argued.

“I’m not a baby,” Tooru responded stubbornly.

“I didn’t say you were. _I_ want to hold your hand,” Hajime frowned.

“Really?” Tooru asked, expression melting slightly.

“Yeah, and I want to take care of you!” Hajime exclaimed a little more proudly.

Tooru’s face fell. He didn’t need to be taken care of. “ _No_!” he yelled, turning away.

Hajime groaned loudly, moving to stand in front of Tooru again. “Don’t be dumb,” he said, flicking Tooru’s forehead in annoyance. He just wanted to hold his hand; why was Tooru being so difficult?

The flick hadn’t been particularly hard but the harsh words combined with the events of the day had turned Tooru moody and the unshed tears suddenly started flowing down his cheeks as large sobs escaped him.

“I’m sorry!” Hajime said quickly, realizing his mistake. He hugged Tooru tightly but his friend wouldn’t stop crying. “I’ll let you play with my Godzilla,” he bargained, praying that their mothers wouldn’t see that he had made Tooru cry. “I won’t hold your hand anymore,” he added in a desperate attempt to calm Tooru down.

It worked because Tooru clutched his shirt tightly, the sobs turning into quieter sniffles. “Just not at school,” he whispered, burying his snot-filled face in Hajime’s shoulder. Hajime nosed at his throat, just like his mother did to him, and even though it didn’t have the same effect, it was enough to calm Tooru down.

 

**♔♔** **9 years – [3]** **♔♔**

“Oneechan told me that it’ll be easy for her to get married because she’s a beta,” Tooru said conversationally, toes digging into the grass underneath the swing set.

“What does that have to do with anything?” Hajime frowned, swinging a butterfly net around carelessly.

There were no butterflies around with the summer sun turning into a cool autumn breeze and at nine years old, Hajime was losing interest in bugs and gaining interest in volleyball. Still, the net had been a gift from Tooru last year so it was special.

“She said she has more choices. She’s fourteen so she’s much smarter than us,” Tooru nodded, although he didn’t quite believe the words himself.

“Not true,” Hajime argued, dropping the net and coming to stand in front of Tooru who was sitting on the swing. “Want me to push you?” he asked, noticing the idle way in which Tooru was shifting back and forth.

“No, you almost threw me off last time,” Tooru reminded pointedly.

“It’s because you weren’t holding on tight. And you kept saying I wasn’t doing it hard enough,” Hajime rolled his eyes.

Tooru huffed in response. His eyes shifted to the empty swing next to him and before he could even ask Hajime to sit with him, his friend had taken the seat up.

“Do you think I’m going to be a beta too?” Tooru asked curiously.

They had started learning about their second genders in school last year and although it was still confusing, he knew enough to talk about it. Both his parents were betas and his sister too, which made it likely that he’d be one.

“Doesn’t matter,” Hajime shrugged.

“Why not?” Tooru glared, annoyed at being brushed off.

“Because I’m going to marry you, anyway,” he stated.

The ease with which he said the words took Tooru by surprise and a deep flush turned his face impossibly red.

“No way! Then we’d have to _kiss_ ,” Tooru spluttered, thinking back to all the things he’d seen his parents do and wondering how that would feel like with Hajime.

“ _So_?” Hajime argued. “I’ll kiss you now if you want,” he shrugged.

“Stop that,” Tooru laughed, jumping off the swing and putting some distance between them.

All that did was spur Hajime to chase him, which ended with them playing an impromptu game of tag, Tooru screaming for Hajime to stay away and Hajime threatening to put a beetle down his shirt if he didn’t stop.

When Hajime finally tackled him to the ground, Tooru couldn’t help but notice that their faces were very close together and that maybe kissing Hajime wasn’t such a bad thought after all.

 

**♔♔** **15 years – [4]** **♔♔**

“Tooru?” Hajime called, cornering him by his locker after school.

He knew that Tooru had a doctor’s appointment that morning because he hadn’t been feeling well all of yesterday; being in different classes meant that this was the only time Hajime could see him since he had come to school after the lunch break.

“Don’t call me that,” Tooru angered.

Hajime felt the sudden urge to wrap his arms around Tooru’s shoulders and bury his nose in his neck the way they used to when they were kids. They hadn’t done that since Hajime had presented as an alpha though and he missed it, if he was being honest with himself.

“Why not? I’ve always called you that,” he reminded.

“Because people will assume I’m your mate,” Tooru replied, shutting his locker closed with far more force than was necessary.

He had cleaning duty today and Hajime had waited up for him, which was why the school was as deserted as it was. It was a good thing too, because Tooru had that look in his eyes, stubborn and unyielding, just like he got whenever they lost a volleyball match and he put the blame on himself.

“You’re an omega then?” Hajime asked knowingly.

He had presented not long after his fourteenth birthday but they were fifteen now and Tooru was a late bloomer by all standards. Everyone had assumed it was because he would present as an alpha, just like Hajime had, although his was more complicated because both his parents were betas and Hajime’s father was an alpha.

No one had imagined that Tooru would present as an omega although Hajime couldn’t deny that he had selfishly hoped that he would ever since Hajime had learned he was an alpha.

Seeing the angry look on his best friend’s face however made him feel guilty, which was the only reason he blurted out, “Would that be so bad?”

“What?” Tooru asked, looking up to meet Hajime’s eyes for the first time since the conversation had started.

He had such a powerful gaze, eyes swirling in a whirlpool of brown. It made Hajime’s confidence waver and he realized just how unconventional of an omega Tooru really was.

“Would it be so bad to be my mate?” Hajime repeated nervously. This wasn’t how he had expected to confess.

“You’re my best friend,” Tooru said, and Hajime felt himself lose all hope with those four words. “But I can’t belong to anyone. I’m sorry,” he apologized, looking away. “I have to ask sensei about the work I missed this morning,” he added, giving Hajime an out from the awkwardness.

“I’ll see you tomorrow then,” he agreed, stuffing his hands into the pocket of his slacks, turning away before Tooru could see too much of his embarrassment.

He wasn’t sure if it was his imagination or if the smell that lingered after him really was that of his best friend in distress but the hurt in his heart prevented him from turning around and comforting him.

 

**♔♔** **18 years – [5]** **♔♔**

It took Tooru three years to come to terms with the fact that he was an omega. There were always going to be people who would judge him poorly because of it but there were also people like Hajime and the Aoba Johsai volleyball team who wouldn’t dare to treat him differently.

“Can you believe we’re starting university in less than two months?” he asked, flopping down onto Hajime’s bed.

They had gone out to lunch with their friends after the graduation ceremony that afternoon but it was a Friday and Friday evenings were always spent with one another.

Tooru would have been lying if he said Hajime’s confession from three years ago hadn’t been on his mind all through high school – that it wasn’t on his mind _now_. It wasn’t that he hadn’t wanted to be with Hajime back then because he _had_ , but the idea of belonging to someone had spurned him.

Now though, he wished he hadn’t been so full of pride.

They were headed in different directions, separated by distance with Hajime staying in Miyagi and Tooru headed for Tokyo.

That didn’t stop his friend from reaching over and pulling Tooru so he was laying flat against his chest, legs tangled with one another. Tooru couldn’t help the soft purr that escaped him, which only made Hajime thread his hands through his hair and nuzzle him softly, scenting him until the room smelled of firewood and lilies, a mixture of them both.

“Go out with me,” Hajime muttered quietly. “You can’t say you don’t like me,” he added, free hand possessively placed against Tooru’s back.

“I want to,” he admitted, closing his eyes so that he wouldn’t cry. “But I waited too long. You know I wouldn’t last even a day without you if I knew what I had,” he whispered, feeling the heat creep down his face at the admission.

“I’ll wait then,” Hajime promised, so seriously that Tooru couldn’t possibly believe anything else.

“Okay,” he whispered, blinking back the bittersweet tears.

He wanted to selfishly ask Hajime to come with him, but he knew it was his own fault for taking so damn long to understand what that feeling in his chest whenever he was around Hajime meant.

He wanted to say _something else_ , something more reassuring, but he couldn’t find the words, so he clung to Hajime, breathing him in deeply and waited for his friend to push him away.

But that didn’t happen, like it never did, and when March turned to April, it was Tooru who pushed away, _unwillingly so_ , while trying his hardest to stake his claim.

 

**♔♔** **22 years – [+1]** **♔♔**

Tooru hadn’t realized how difficult being away from Hajime would be, even if they weren’t mates. His best friend had always been the most stable presence in his life, always there for him when he needed him the most. Whether he was scared, or angry, or upset, it was Hajime – _his scent_ – that could calm him down.

While he had never explicitly helped Tooru through his heat – that was one line they weren’t willing to cross, no matter how _affectionate_ their friendship had always been – it was the fact that he _could_ , and that he was near enough for Tooru to reach him for help that had kept him grounded.

He was lucky that his heats were infrequent, but the first time it happened while he was in Tokyo had been the worst heat he had experienced since his very first one, even with suppressants and various painkillers.

He had ended up crying, until his roommate, another omega, had calmed him down. The next time Hajime had come to visit, Tooru had clung to him and in a state of frenzy had asked him to never leave him, which Hajime reassured with unwavering confidence.

For the past four years, Hajime hadn’t left him, not when Tooru was feeling the most vulnerable and now, having finally graduated, he couldn’t contain the excitement of what was to come.

“Congrats, Oikawa,” Hajime ruffled his hair, pulling him into a hug as Tooru walked towards him, diploma in hand.

His parents and sister were standing not too far off, allowing Tooru and Hajime to savour their moment together. He had gone to Hajime’s graduation last week, so it was no surprise that his best friend was at his, but it didn’t stop Tooru from feeling immensely elated all the same.

“Don’t call me that,” Tooru frowned, slightly miffed at the unfamiliar use of his surname.

Hajime chuckled, gently cupping Tooru’s cheek with his large palm. “Congrats, Tooru,” he corrected with a smile before leaning down and kissing him in front of everyone. Tooru couldn’t help but melt at the touch, itching to get closer. It was something he had dreamt of consistently for the past four years and now, there were no _what ifs_ left to worry him.

“That wasn’t a proper confession,” Tooru sighed when they pulled apart, eyes glassy, cheeks dusted in a rosy pink.

“Go out with me. Be my mate.” Hajime said easily.

This time, Tooru could do nothing but nod, happy tears slipping down his face as he threw his arms around Hajime’s shoulders and squeezed him tight, ready to never let him go.

 

**♔♔** **25 years – [Bonus]** **♔♔**

An omega on centre court, playing for the Japanese men’s Olympic volleyball team was almost as rare as a win for Japan in the very same year. But there Tooru was, standing proudly with his teammates, a gold medal hanging around his neck while Hajime watched fondly from the stands.

As the arena cleared out, he saw Tooru beckon him forward and the security personnel standing guard let him through onto the court. His best friend – _boyfriend_ – was sweaty but that didn’t stop Hajime from embracing him, keeping mind that this was a public place.

“You were amazing, I’m so proud of you,” he smiled.

“ _Us_ ,” Tooru clarified. “I couldn’t have done this without your support,” he reminded, pulling the medal off of his neck and placing it around Hajime’s own, smiling sunnily.

The sincerity of the action had Hajime’s mind reeling from the affection. He felt his heart thunder against his chest and he was certain Tooru could hear how loud it was too.

He took the medal and pulled it off his neck, ignoring the look of confusion Tooru gave him before dropping to one knee and draping the ribbon across Tooru’s hands. “Please marry me?” he asked, swallowing the nervous lump in his throat.

“H-Hajime,” Tooru stuttered, reaching down to pull him up until they were level. “Of course— _yes_.”

“Really?” Hajime asked, stunned by the response.

“What do you mean _really_. You’re the one who asked,” Tooru laughed.

Hajime flushed, rubbing the back of his neck sheepishly, a tingling feeling run down his spine when he touched the mark Tooru liked to place on him often.

“It took you forever to say you’d go out with me. I thought we’d be dead before you agreed to marry me,” he teased.

“I know what I want now,” Tooru promised. “I have for a while,” he added.

Hajime didn’t have to admit that he’d have waited a thousand lifetimes for Tooru to know what he wanted for the two of them to realize that he would have. But he was happy that he didn’t have to wait that long and that he could be with Tooru for the rest of his life; for _eternity_.

**Author's Note:**

> kudos and comments are very much appreciated! ♡


End file.
